Title: Nanoplasmonics for Biology
Speaker: Dr. Nagarajan Subramaniyam, Xfold imaging Oy, Finland
Abstract: I will present my work in the area of nanoplasmonics for bioimaging and diagnosticapplications. The focusof the specific area of interest:Surface-enhanced fluorescenceimaging for focal adhesion proteinsin cells,bacteria (mycobacterium), SARS-CoV-2 virus, and nonlinearplasmonics (coherent anti-StokesRaman scattering and second harmonic generation microscopy) for lipid imagingand stain-free histopathology diagnostic applications.
Fluorescence microscopy is a widely used method for imaging various biological samples. A major limitation of present widefield and confocal fluorescence microscopy is the lackof sensitivity. The resolution of the confocal fluorescence microscope is limited to ~300 nm in the focal plane (xy) and ~600 nm in the optical axis (z). Different types of patterned metal surfaces and metallic nanoparticles have been demonstrated to enhance the fluorescence signal, but these enhancements have typically not been significant and are concentrated to “hot spots” around the metal features. In my talk, I will presentthenanoplasmonicslides designed to enhance the sensitivity of fluorescence microscopy in a close range from the slide surface, in order to better visualize the focal adhesionsproteins in cells and single virion. The nanoplasmonicslides provide a significantly enhanced fluorescence signal, allowing a lower laser power to be used in imaging,and enabling improved imaging and high sensitivity in diagnostics.
Coherent anti-Stoke’s Raman scattering (CARS) microscopy has been widely used as a label-free tool for visualizing lipids in biological samples. The major challenge in CARS microscopy is to increase the detection sensitivity to nanomolar levels or visualizethe plasma membrane. Iwill show the nonlinearplasmonicslides designed to enhance the sensitivity of the CARS microscopy in order to visualize the cell plasma membrane.The nonlinear plasmonicslides provide a new avenue in CARS microscopy imagingwithnanomolar sensitivity for biologists and clinicians, with potentially high impact on the healthcare industry.